Structure dependency of the reactivity of aromatic hydrocarbons involving the formation of oxygenated polycyclic aromatic hydrocarbons (OPAHs)

The reactivity of six aromatic hydrocarbons (benzene, naphthalene, anthracene, toluene, indene, and fluorene) with O or OH, which are involved in the formation of oxygenated polyaromatic hydrocarbons (OPAHs), were compared using quantum chemistry calculations to reveal the structure dependency. We revealed that comparing C6H6, C10H8, and C14H10, the barrier height becomes lower as the molecular size increases. Comparing C9H8 and C13H10, which contain a 5-membered ring, C9H8 is more reactive with both O and OH. In addition, possible reaction paths for the formation of indanone, an OPAH which is observed in combustion, from C9H8 are found.